Riverbank erosion and recession in the Ottawa area

Abstract

Landsliding has been a major problem to property owners and developers along the Ottawa River and its tributaries. A study of aerial photographs of a section of the Ottawa River near Ottawa, taken over a period of nearly 50 years, has identified a cyclic relationship between the processes of erosion, landsliding, and riverbank recession. Using detailed measurements of topographic maps and of contours plotted from the aerial photographs, a physical model has been proposed to describe the erosion–landsliding cycle. For the area under study the average cycle return period is estimated to be about 60 years, and the long-term rate of riverbank recession is about 0.4 m/year.